Agar ready to roll if picked: Mitch Marsh

Ashton Agar has played only one first-class game since recovering from a broken finger but in it he delivered 50 overs of impressive left-arm spin, according to Western Australia skipper Mitch Marsh.

Agar will play his first Test on home soil if he is selected for the Ashes finale, which starts at the SCG on Thursday.

It remains a big if given Mitchell Starc's desperation to return from injury and predictions of a pitch that could offer more assistance to pacemen than tweakers.

Questions have also been raised about whether Agar is ready for the unique pressure of a Test, having played three Big Bash League games and the single Sheffield Shield fixture since he returned from injury.

Agar insisted on Sunday he is ready to go. Marsh, who captained WA in the MCG match in which the 24-year-old returned from injury, agrees.

"I watched him bowl 50 overs at the MCG against Victoria and he bowled beautifully on a wicket very similar to the one we played on last week (during the fourth Test)," Marsh told reporters in Sydney.

"He's bowling very well and hopefully if he does get his chance he's able to take it.

"He's also shown over a long period of time he can bat and he could play as an allrounder."

Marsh is ready to step up and deliver more overs if Agar replaces Jackson Bird in the XI, admitting he is yet to deliver his best with the ball during the current series.